Recent advances in molecular and cellular biology, the emergence of more sophisticated animal models of human disease and the development of sensitive, high-resolution imaging systems enable the study of pathophysiology noninvasively in unprecedented detail. The overall goal of our work is to develop new techniques and agents to study human disease through imaging. We concentrate on two areas, i.e., cancer and central nervous system processes. Our work extends from basic chemical and radiochemical synthesis to clinical translation.

Current synthetically oriented projects include the development of radiopharmaceuticals for positron emission tomography (PET) and single photon emission computed tomography (SPECT) as well as optical imaging agents to be used for surgical guidance and nanomedicines. Such agents typically bind receptors or enzymes. One major effort involves developing a series of urea derivatives that have a high affinity for the prostate-specific membrane antigen (PSMA), also known as glutamate carboxypeptidase II, as leads for imaging agents for prostate cancer and psychiatric disease. Several of those agents are in clinical trials. We have recently embarked on a program to develop radioimmunodiagnostic and low molecular weight imaging agents for chemokine receptors, and have developed a general technique for molecular-genetic imaging and therapy of cancer.

Human PET studies are also a priority, and we have several protocols for studying neurotransmission and inflammation in a variety of central nervous system pathologies including AIDS dementia and traumatic brain injury. We have also developed new methods to image infection and to image and treat virs-associated tumors - both of which are in clinical trials underway at Johns Hopkins and elsewhere.